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Enabling SpringAware Objects

You can mark Hazelcast Distributed Objects with @SpringAware if the object wants to apply:

  • bean properties

  • factory callbacks such as ApplicationContextAware, BeanNameAware

  • bean post-processing annotations such as InitializingBean, @PostConstruct.

Hazelcast Distributed ExecutorService, or more generally any Hazelcast managed object, can benefit from these features. To enable SpringAware objects, you must first configure HazelcastInstance using hazelcast namespace as explained in Configuring Spring and add <hz:spring-aware /> tag.

SpringAware Examples

  • Configure a Hazelcast Instance via Spring Configuration and define someBean as Spring Bean.

  • Add <hz:spring-aware /> to Hazelcast configuration to enable @SpringAware.

    <beans xmlns="http://www.springframework.org/schema/beans"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
           xmlns:context="http://www.springframework.org/schema/context"
           xmlns:hz="http://www.hazelcast.com/schema/spring"
           xsi:schemaLocation="http://www.springframework.org/schema/beans
                    http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
                    http://www.springframework.org/schema/context
                    http://www.springframework.org/schema/context/spring-context-3.0.xsd
                    http://www.hazelcast.com/schema/spring
                    http://www.hazelcast.com/schema/spring/hazelcast-spring.xsd">
    
        <context:component-scan base-package="..."/>
    
        <hz:hazelcast id="instance">
            <hz:config>
                <hz:spring-aware />
                <hz:cluster-name name="dev"/>
                <hz:network port="5701" port-auto-increment="false">
                    <hz:join>
                        <hz:multicast enabled="false" />
                        <hz:tcp-ip enabled="true">
                            <hz:members>10.10.1.2, 10.10.1.3</hz:members>
                        </hz:tcp-ip>
                    </hz:join>
                </hz:network>
                ...
            </hz:config>
        </hz:hazelcast>
    
        <bean id="someBean" class="com.hazelcast.examples.spring.SomeBean"
          scope="singleton" />
        ...
    </beans>

Distributed Map SpringAware Example:

  • Create a class called SomeValue which contains Spring Bean definitions like ApplicationContext and SomeBean.

    @SpringAware
    @Component("someValue")
    @Scope("prototype")
    public class SomeValue implements Serializable, ApplicationContextAware {
    
        private transient ApplicationContext context;
        private transient SomeBean someBean;
        private transient boolean init = false;
    
        public void setApplicationContext( ApplicationContext applicationContext )
            throws BeansException {
            context = applicationContext;
        }
    
        @Autowired
        public void setSomeBean( SomeBean someBean)  {
            this.someBean = someBean;
        }
    
        @PostConstruct
        public void init() {
            someBean.doSomethingUseful();
            init = true;
        }
    }
  • Get SomeValue Object from Context and put it into Hazelcast Distributed Map on the first member.

    HazelcastInstance hazelcastInstance =
        (HazelcastInstance) context.getBean( "instance" );
    SomeValue value = (SomeValue) context.getBean( "someValue" );
    IMap<String, SomeValue> map = hazelcastInstance.getMap( "values" );
    map.put( "key", value );
  • Read SomeValue Object from Hazelcast Distributed Map and assert that init method is called since it is annotated with @PostConstruct.

    HazelcastInstance hazelcastInstance =
        (HazelcastInstance) context.getBean( "instance" );
    IMap<String, SomeValue> map = hazelcastInstance.getMap( "values" );
    SomeValue value = map.get( "key" );
    Assert.assertTrue( value.init );

ExecutorService SpringAware Example:

  • Create a Callable Class called SomeTask which contains Spring Bean definitions like ApplicationContext, SomeBean.

    @SpringAware
    public class SomeTask
        implements Callable<Long>, ApplicationContextAware, Serializable {
    
        private transient ApplicationContext context;
        private transient SomeBean someBean;
    
        public Long call() throws Exception {
            return someBean.value;
        }
    
        public void setApplicationContext( ApplicationContext applicationContext )
            throws BeansException {
            context = applicationContext;
        }
    
        @Autowired
        public void setSomeBean( SomeBean someBean ) {
            this.someBean = someBean;
        }
    }
  • Submit SomeTask to two Hazelcast Members and assert that someBean is autowired.

    HazelcastInstance hazelcastInstance =
        (HazelcastInstance) context.getBean( "instance" );
    SomeBean bean = (SomeBean) context.getBean( "someBean" );
    
    Future<Long> f = hazelcastInstance.getExecutorService("executorService")
        .submit(new SomeTask());
    Assert.assertEquals(bean.value, f.get().longValue());
    
    // choose a member
    Member member = hazelcastInstance.getCluster().getMembers().iterator().next();
    
    Future<Long> f2 = (Future<Long>) hazelcast.getExecutorService("executorService")
        .submitToMember(new SomeTask(), member);
    Assert.assertEquals(bean.value, f2.get().longValue());
Spring managed properties/fields are marked as transient.